


Hypnos

by overlordy



Category: Undertale (Video Game)
Genre: Angst, Bondage, Choking, Dubious Consent, M/M, PWP, Plot What Plot/Porn Without Plot, Rough Sex, Tentacles, but im putting it there just in case, dubcon, hot void sex, not really - Freeform, this is not a nice fic, with said tentacles
Language: English
Status: Completed
Published: 2015-11-18
Updated: 2015-11-18
Packaged: 2018-05-02 05:44:30
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,124
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5236499
Author URL: https://archiveofourown.org/users/overlordy/pseuds/overlordy
Summary: <blockquote class="userstuff">
              <p>Sans usually doesn't dream. When he does, he's plagued by nightmares of past timelines.</p>
<p>Except this time.</p>
            </blockquote>





	Hypnos

**Author's Note:**

> hello i am here and i am sinning.
> 
> originally a fill for the undertail kink meme and i am here displaying my trash lifestyle

Darkness swam in Sans’s vision, cold and suffocating and unwelcoming. It pressed in on all sides, almost claustrophobic, and crawled up his spine.

Wait.

Something actually  _ was _ crawling up his spine, slimy and squirming, like a slug. Sans jumped and tried to scramble away, but whatever it was wrapped around his femur and pulled him to the ground. His skull cracked against the dark surface he had been standing on and he groaned, fingers scrambling for purchase against nothing.

** “WHY ARE YOU RUNNING?” **

The voice sent a violent shudder through his body. It was wrong, like he was listening to an illegal radio station. The jagged voice assaulted his hearing and his hands flew to his skull to block out the noise, but two more of the slimy things caught his wrists and pinned his arms down. He gasped and squirmed, yanking and tugging at his bonds, instinct screaming  _ wrong wrong get away- _

** “SANS, LOOK AT ME.” **

It knew his name. Eyes wide, Sans found himself craning his neck over his shoulder.

He knew that face. He had forgotten. How could he forget?

“g-gaster?”

He stared up at his old boss’s grinning visage. Gaster's smile was warped and twisted into something corrupt and unnatural. Two cracks ran along his skull and occasionally leaked a viscous, black fluid. Sans winced in sympathy.

** “OH. YOU REMEMBER.” ** Gaster hissed, his crackling voice curling around Sans. No, it was a mass of dripping tendrils, wrapping tightly around his bones and tearing away his clothes. Sans’s breathing quickened in panic as the oily appendages squeezed around his radius and ulna, sending white-hot pain coursing through him.

“g-gaster, wait-”

Another hiss and another squeeze. Gaster paid his stammered pleas no mind. The tips of several other tendrils traveled down his spine, leaving behind a sticky trail of black goop. Sans trembled, straining against the black masses wrapped around his limbs, to no avail.

He was trapped.

“h-hold on a minute! ga-”

A mass of writhing tentacles shot up into his to cage with explosive force, choking off his last cry for mercy. Stars danced in his vision at the intense pleasure coupled with an overbearing pressure. He felt ready to burst, to come apart in a shower of bone shards, but the things inside him never pressed hard enough to break. Sans moaned, loud, the hollow noise echoing in the empty, dark landscape. He felt himself being lifted, the movement surprisingly gentle. He didn't resist.

** “ISN’T THAT BETTER?” ** Sans weakly nodded and the mass of appendages in his rib cage gave a pulse of approval which had the smaller skeleton crying out in ecstasy. He was turned to face Gaster, suspended in midair.

It hurt to look at him. Sans cast his gaze downwards as he was bombarded with happy memories of the two working together. He caught a flash of a frown before Gaster's cold hands gripped his cheeks and forced eye contact.

** “DON’T LOOK AWAY.” **

Sans felt tears welling up in his eye sockets. “i’m just going to forget again.”

Gaster’s expression softened along with his grip on Sans’s face. His touch turned into soft caresses, his thumb tracing the outline of Sans’s permanent grin. **“YOU WILL NOT. I TRUST YOU.”** Sans fought back a sob, his arms trembling with the weight of holding himself up. The tendrils around his legs shifted and more appeared, until he was supported by a clump of slimy darkness. The movement of the shadows in his chest stilled completely.

“...gaster,” he gasped, voice trembling with sorrow. “please.”

Gaster smiled and resumed his ministrations with twice the amount of enthusiasm as before. Tears streamed unhindered down his cheeks as every inch of him was assaulted with pleasure. He squirmed, helpless, as the tendrils inside him curled and stroked around his ribs, the bones creaking under the pressure, but not enough to give. The sensation teetered on the edge of pain and coalesced with pleasure, creating an intense situation that had Sans simultaneously wanted to get away, but also press closer. Slick limbs wrapped around his spine and flicked sharply against his vertebrae. The harsh touch had him arching his back and moaning, drool dribbling unbidden from his teeth and mixing with the thick secretions Gaster left behind on his bones.

Gaster's hands moved down from his face, and when Sans did not look away from those hollow eyes, travelled down to his hips. Those cold hands groped at his pelvis and worked sensitive bone after bone with intelligent, seeking fingers, as if Gaster knew every exact way to make Sans come apart at the seams. Gaster's sharp nails scraped against his bones, sending a tingle of pain up his spine. He cried out as Gaster's fingers dug in deeper, unrelenting, his empty eye sockets taking in every passionate expression with longing.

** “IT HAS BEEN SO LONG…” ** One hand traveled up the sides of his pelvis, greedy for contact.  ** “I MISSED SEEING YOU LIKE THIS.” ** His fingers returned to Sans’s face and pressed against his teeth. Sans obediently parted his jaws and Gaster’s fingers slid inside of his mouth, pressing against the magical tongue Sans summoned. Gaster exhaled, the noise wet and rattling and dead, as Sans curled his tongue around the former scientist’s thin fingers.  ** “SO BEAUTIFUL.” ** Gaster removed his fingers, his tone reverent. Then his hand wrapped around Sans’s neck, nails digging into his spinal column. Sans choked out a moan at the tight, restraining grip. If Gaster were to squeeze just a little tighter, he could easily snap the fragile vertebrae. But, against all reason, Sans knew he wouldn’t.

Sans’s cries escalated, pushed further and further to the edge as Gaster’s tendrils stroked along his sternum and coiled tightly around his ribs. The assault on his senses from all sides was almost too much, yet not enough.

“ _ aaahn… _ g-gaster! i-i need-”

Gaster complied, the movements of his hands increasing and the tendrils stroking his bones writhing with violent intensity. Sans shook, his cries unrestrained, desperate and wanton and filled with need. His pleasure reached its peak, cutting off his screams and stilling his desperate writhing as searing hot pleasure flooded through him.

He slumped against his bonds, bone tired (heh). His eyes closed but Gaster did not reprimand him. The tendrils slid out of his ribs, making him shiver from sensitivity, and released him. He dropped to the floor-

-and woke up, safe in his bed, in his home, in Snowdin. His hands shook. His bones felt sticky and disgusting and his shorts had a damp patch from where he had cum in his sleep.

He resigned himself to a week or two of no sleep as he stood. He felt the lingering touch of a ghostly hand against his cheek.


End file.
